From all this the Blagojevich scandal is an unwanted distraction. It is a reminder that, for all his inspirational talk of hope and change, Obama, like Blagojevich, are both products of Chicago Democratic politics, which is capable of producing leaders both sublime and sordid.

Obama has not always avoided the latter. For 20 years he attended the church of the Rev. Jeremiah Wright, now thrown under the bus, and for more than a decade engaged in mutually beneficial exchanges political and financial with the political fixer Tony Rezko, now in federal custody.

Blagojevich, never a close political ally, has now been thrown under the bus, too, and seems likely to share Rezko's fate. Obama fans can point out, truthfully, that other revered presidents had seamy associates and made common cause on their way up with men who turned out to be scoundrels. Franklin Roosevelt happily did business with Chicago Mayor Ed Kelly, though warned that he was skimming off money from federal contracts. John Kennedy no more thought to deny a request from the Mayor Daley of his day than Obama has thought to buck the Mayor Daley of his.

But as Kennedy supposedly said of a redolent Massachusetts politician, "Sometimes party loyalty asks too much." The man in question was the Democratic nominee for governor and was not elected. Until Patrick Fitzgerald released his tapes, Barack Obama never said the same of Rod Blagojevich.

Obama has profited greatly from his careful climb through Chicago politics. But there is an old saying that in politics nothing is free -- there is just some question about when you pay the price. Obama is paying it now.